Preparation and Property of Electrodeposited Zn-Fe-SiO2 Composite Coating
Electrodeposited Zn and Zn-Fe alloy have been applied widely to protect steel from corrosion, but the property of coating still needs to be improved. In this paper, Zn-Fe-SiO2 composite coatings are electrodeposited from Zn-Fe alloy electrolyte containing SiO2 particles. Zinc based coatings with Fe% >1%(mass) are deposited from sulfate bath, and coatings with Fe% <1%(mass) are deposited from chloride bath. Particle content in the composite coating generally increases with particle concentration under an adequate agitation and then tends to saturation. The optimum particle content in the composite coating is 0.5%(mass). Corrosion resistance, porosity, hydrogen embrittlement and surface morphology of Zn-Fe-SiO2 composite coatings have been tested and compared with electrodeposited Zn and Zn-Fe alloy. The data implies that Zn-Fe-SiO2 composite coating has the best corrosion resistance, lowest porosity, lowest hydrogen content and the finest crystal. All the results show that Zn-Fe-SiO2 composite coating is satisfactory to be used as anti-corrosion material for steel and has a great future in application.
M.K. Lei, X.P. Zhu, K.W. Xu and B.S. Xu
Y. Y. Fan, Y. J. Zhang, P. Dong, "Preparation and Property of Electrodeposited Zn-Fe-SiO2 Composite Coating", Key Engineering Materials, Vols. 373-374, pp. 212-215, 2008